--- title: "Enhancing Industrial Efficiency: Variable Frequency Drives" description: Explore the advantages and challenges of Variable Frequency Drives (VFDs) in industrial motor systems. Learn how AEGIS® Shaft Grounding Rings can protect motor bearings, reduce costs, and prevent downtime. image: https://blog.est-aegis.com/hubfs/vfd_dreamstime_m_88280340.jpg --- [![Electro Static Technology](https://blog.est-aegis.com/hubfs/raw_assets/public/public/images/electro-static-technology.svg "Electro Static Technology")](https://www.est-aegis.com/) [![Aegis](https://blog.est-aegis.com/hubfs/raw_assets/public/public/images/Aegis.svg "Aegis")](https://www.est-aegis.com/) - [+1 866-738-1857](tel:+1%20866-738-1857) - [Products](https://www.est-aegis.com/products/) - [AEGIS® SGR – for motors under 500 HP/375 kW](https://www.est-aegis.com/product/sgr/) - [AEGIS® uKIT – for common NEMA/IEC frame size](https://www.est-aegis.com/product/sgr-ukit/) - [AEGIS® RPPR – for reactor recirculating pumps](https://www.est-aegis.com/rppr-resources/) - [AEGIS® EV and EVO Rings - for electric vehicles](https://www.est-aegis.com/product/ev-evo-rings/) - [AEGIS® PRO Series – for motors over 300 HP/225 kW](https://www.est-aegis.com/product/pro-series/) - [Shaft Voltage Testing and Accessories](https://www.est-aegis.com/product/mounting-accessories/) - [Online Product Catalog](https://catalog.est-aegis.com/) - [AEGIS® 2-Year Extended Warranty](https://www.est-aegis.com/product/extended-warranty/) - [Applications](https://www.est-aegis.com/applications/) - [Electric Vehicle Solutions](https://www.est-aegis.com/applications/electric-vehicle-solutions/) - [Food & Beverage](https://www.est-aegis.com/applications/food-beverage/) - [HVAC](https://www.est-aegis.com/applications/hvac/) - [Industrial & Chemical](https://www.est-aegis.com/applications/industrial-chemical/) - [Other Industries](https://www.est-aegis.com/applications/other-industries/) - [Power Generation & Renewable Energy](https://www.est-aegis.com/applications/power-generation-renewable-energy/) - [Transportation](https://www.est-aegis.com/applications/transportation/) - [Water Treatment](https://www.est-aegis.com/applications/water-treatment/) - [Bearing Protection](https://www.est-aegis.com/bearing-protection/) - [Shaft Voltage & Bearing Currents](https://www.est-aegis.com/bearing-protection/shaft-voltage-and-bearing-currents/) - [Fluting & Bearing Inspection](https://www.est-aegis.com/bearing-protection/fluting-and-bearing-inspection/) - [Best Practices & Installation](https://www.est-aegis.com/bearing-protection/best-practices-and-installation/) - [Resources](https://www.est-aegis.com/resources/) - [AEGIS® Bearing Protection Handbook](https://www.est-aegis.com/resources/handbook/) - [IEEE-841, Hazardous Locations, & AEGIS®](https://info.est-aegis.com/technical-codes-and-ieee-841-standards) - [Recorded Webinars Library](https://www.est-aegis.com/resources/recorded-webinars/) - [Installation Instructions](https://www.est-aegis.com/resources/installation-instructions/) - [Videos](https://www.est-aegis.com/resources/videos/) - [Technical Papers](https://www.est-aegis.com/resources/technical-papers/) - [Case Studies](https://www.est-aegis.com/resources/case-studies/) - [Specifying AEGIS®](https://www.est-aegis.com/resources/specifying-aegis/) - [Request Training](https://www.est-aegis.com/resources/training/) - [Product Sheets](https://www.est-aegis.com/resources/product-sheets/) - [About](https://www.est-aegis.com/about/) - [News](https://blog.est-aegis.com/) - [Tradeshows](https://www.est-aegis.com/about/tradeshows/) - [Blog](https://blog.est-aegis.com/) - [Where to Buy](https://www.est-aegis.com/where-to-buy/) - [Distributors](https://www.est-aegis.com/where-to-buy/distributors?type=Distributor) - [Trained Installers](https://www.est-aegis.com/where-to-buy/installers?type=Installer) - [Explosion Proof Installers](https://www.est-aegis.com/where-to-buy/installers?type=Explosion%20Proof%20Installer) - [Motors & Seals with AEGIS® Installed](https://www.est-aegis.com/where-to-buy/oems-with-aegis/) [Contact Us](https://www.est-aegis.com/contact/) - [+1 866-738-1857](tel:+1%20866-738-1857) # What is a Variable Frequency Drive (VFD)? [Home](https://www.est-aegis.com/) » [Blog](https://blog.est-aegis.com/) » What is a Variable Frequency Drive (VFD)? [AEGIS](https://blog.est-aegis.com/author/estaegis) Jun 4, 2024 In today’s rapidly advancing technological landscape, the efficiency and control of industrial equipment are paramount. One technology at the forefront of enhancing motor performance and energy conservation is the variable frequency drive (VFD).  In this post, we will look more at these common motor controllers.   ## Understanding Variable Frequency Drives ![vfd_dreamstime_m_88280340](https://blog.est-aegis.com/hs-fs/hubfs/vfd_dreamstime_m_88280340.jpg?width=400&height=265&name=vfd_dreamstime_m_88280340.jpg)A variable frequency drive is an electronic system that controls the speed of an AC motor by varying the frequency of electricity supplied to it. VFDs allow for precise control over motor speed and torque, which has two big advantages.  For one, precise speed or torque control is needed for many industrial processes.  And running motors at reduced speed saves large amounts of energy. ### How Does a VFD Work? VFDs have three core components: - **Rectifier:** The first stage involves converting AC power into DC power using diodes. - **DC Bus:** The DC power is then smoothed out to create a stable voltage using capacitors. - **Inverter:** Finally, this DC is converted back into variable frequency AC power using switches such as IGBTs (Insulated Gate Bipolar Transistors). Most modern VFDs use pulse width modulation to control their output frequency. Their output is a series of pulses in each phase.  VFDs can efficiently manage motor speed and torque by varying the pulse width (duration) and timing. ### Advantages of Using VFDs The use of VFDs offers several technical advantages that improve overall system performance and cost-efficiency: - **Energy Savings:** Significant energy savings are achieved by operating motors at needed speeds rather than constant full speed. - **Longer Motor Life:** In applications with many start/stop cycles, gradually ramping the speed up and down reduces mechanical stress on motor components. - **Improved Process Control:** With precise speed control, processes can be optimized for better quality and throughput. - **Reduced Maintenance Costs:** Lower and smoothly varying speeds mean less wear and tear on gears, belts, and bearings. These benefits underscore why VFDs are a common component of modern industrial electric motor systems.   ## The Impact of VFDs on Motor Bearings While VFDs offer numerous benefits, they do come with their own challenges. One such problem is electrical bearing damage. The pulsed nature of drives’ output induces unwanted voltage on the shafts of motors on VFDs. If not adequately managed, this voltage will discharge through the bearings, causing electrical damage. Some of the problems caused by shaft voltage are: - **Bearing Pitting:** When shaft voltage discharges by arcing through the bearing, it forms microscopic pits and fusion craters on the bearing surfaces. - **Grease Degradation:** This arcing chemically degrades grease, reducing its lubricating properties. It also leads to contamination with metal particles “blasted out” of the pits described above. - **Cumulative Damage:** Over time, continued electrical erosion can lead to bearing fluting, resulting in increasing noise and premature bearing failure. To combat these problems, the AEGIS® Shaft Grounding Ring provides a safe discharge path for shaft voltage, through the ring instead of the bearings. Our rings employ proprietary conductive microfibers that channel discharge current away from the bearings.   ## ![AEGIS_SGR-Grp-2016](https://blog.est-aegis.com/hs-fs/hubfs/Imported_Blog_Media/AEGIS_SGR-Grp-2016.jpg?width=350&height=280&name=AEGIS_SGR-Grp-2016.jpg)AEGIS® Shaft Grounding Rings and Your Bottom Line With AEGIS® Shaft Grounding Rings integrated into your systems, you can reduce motor repair/replacement costs and, more importantly, protect your operations from the huge costs of unplanned downtime. Explore our [Bearing Protection Handbook](https://www.est-aegis.com/resources/handbook/) for more information, or [contact us](https://www.est-aegis.com/contact/) today to find out how to integrate AEGIS® technology into your operations for lasting benefits.   AEGIS rings also come with a [2-year extended warranty](https://www.est-aegis.com/product/extended-warranty/) against bearing fluting damage.  No other form of shaft grounding comes with a warranty like this. [![2-Year Extended Warranty](https://no-cache.hubspot.com/cta/default/20974229/3b258d08-3058-4c7f-a866-2991b627f2e0.png)](https://cta-redirect.hubspot.com/cta/redirect/20974229/3b258d08-3058-4c7f-a866-2991b627f2e0)   To learn more about AEGIS shaft grounding and best practices for electrical bearing protection, [sign up for a training](https://www.est-aegis.com/resources/training/).  We offer monthly live training webinars, and we can also visit your facility to review your exact application. [![Sign Up For Training](https://no-cache.hubspot.com/cta/default/20974229/69dd56c7-bbd1-4ad0-ae5c-29de322039f0.png)](https://cta-redirect.hubspot.com/cta/redirect/20974229/69dd56c7-bbd1-4ad0-ae5c-29de322039f0)   [VFD Bearing Damage](https://blog.est-aegis.com/tag/vfd-bearing-damage), [AEGIS Shaft Grounding Rings](https://blog.est-aegis.com/tag/aegis-shaft-grounding-rings) ### Subscribe To Our Blog ## Read On ### [Accessories to Improve Motor Reliability](https://blog.est-aegis.com/enhance-motor-reliability-with-the-right-accessories?hsLang=en-us) Electric motors are the backbone of practically every industry. From [HVAC systems](https://www.est-aegis.com/applications/hvac/) in commercial... ### [Shaft Grounding Adds Value to Motor Repair](https://blog.est-aegis.com/shaft-grounding-adds-value-motor-repair?hsLang=en-us) Motor repair is a competitive business. Many owners are selling to larger companies in an... ### [Protect Your Electric Motor Bearings with Reliable Shaft Grounding](https://blog.est-aegis.com/protect-your-electric-motor-bearings-with-aegis-shaft-grounding-rings?hsLang=en-us) Are you concerned about damage to your electric motor bearings caused by electrical arcing?... [![Electro Static Energy](https://blog.est-aegis.com/hubfs/raw_assets/public/public/images/logo-est-alt.svg) ![AEGIS](https://blog.est-aegis.com/hubfs/raw_assets/public/public/images/logo-aegis-alt.svg)](https://www.est-aegis.com) 31 Winterbrook Road Mechanic Falls, ME 04256 Phone: [+1 207-998-5140](tel:+1%20207-998-5140) Fax: [+1 207-998-5143](fax:+1%20207-998-5143) Contact Us: [Send Message](https://www.est-aegis.com/contact/) ## Subscribe to Our Emails - [Products](https://www.est-aegis.com/products/) - [AEGIS® SGR](https://www.est-aegis.com/product/sgr/) - [AEGIS® uKIT](https://www.est-aegis.com/product/sgr-ukit/) - [AEGIS® PRO Series](https://www.est-aegis.com/product/pro-series/) - [Testing & Accessories](https://www.est-aegis.com/product/mounting-accessories/) - [Custom Static Solutions](https://www.est-aegis.com/product/custom-static-solutions/) - [Product Catalog](https://catalog.est-aegis.com/) - [AEGIS® 2-Year Extended Warranty](https://www.est-aegis.com/product/extended-warranty/) - [Applications](https://www.est-aegis.com/applications/) - [Electric Vehicle Solutions](https://www.est-aegis.com/applications/electric-vehicle-solutions/) - [Food & Beverage](https://www.est-aegis.com/applications/food-beverage/) - [HVAC](https://www.est-aegis.com/applications/hvac/) - [Industrial & Chemical](https://www.est-aegis.com/applications/industrial-chemical/) - [Other](https://www.est-aegis.com/applications/other-industries/) - [Power Generation & Renewable Energy](https://www.est-aegis.com/applications/power-generation-renewable-energy/) - [Transportation](https://www.est-aegis.com/applications/transportation/) - [Water Treatment](https://www.est-aegis.com/applications/water-treatment/) - [Resources](https://www.est-aegis.com/resources/) - [Request a Training](https://www.est-aegis.com/contact/request-a-training/) - [AEGIS® Bearing Protection Handbook](https://www.est-aegis.com/resources/handbook/) - [Videos](https://www.est-aegis.com/resources/videos/) - [Technical Papers](https://www.est-aegis.com/resources/technical-papers/) - [Case Studies](https://www.est-aegis.com/resources/case-studies/) - [Specifying AEGIS®](https://www.est-aegis.com/resources/specifying-aegis/) - [Product Sheets](https://www.est-aegis.com/resources/product-sheets/) - - - Copyright 2022 Electro Static Technology. All rights reserved. Made in America. - [Privacy Policy](https://www.est-aegis.com/privacy-policy/) - [Terms and Conditions](https://www.est-aegis.com/terms-and-conditions/) - [Sitemap](https://www.est-aegis.com/sitemap/)